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Radiation Symbol
Obtain legal approval to store and handle isotopes
Use occupancy less area for storage
Follow suggested design of storage, otherwise obtain competent approved alternative design
Store radiography cameras / sources in pit in a separate storage room
Keep the storage room under lock & key always
SAFE STORAGE OF SOURCE
Continue…
Check proper storage of source inside camera after every use.
Use survey meter check radiation leakage
Post Warning signs along with radiation symbol
Operator shall maintain log book to record usage of the equipment
SAFE STORAGE OF SOURCE
Continued.
STORAGE OF RADIO ACTIVE CAMERA & SOURCE
Layout Plan for Radiography Camera Store Room
The following information to logged:
Date & time of taking the source with camera
Type & strength of sources
Model & serial no. of camera
Name of the radiographer
Location of use
Type & number of exposure
Duration of use
Date & time of return of the source with camera
LOG BOOK
Permissible Leakage Level of Camera
Measurement DistanceAveragemR/hr
MaximummR/hr
5 cm from Surface 20 100
1m from source position 2 10
Safe Work Practices
Carry out Radiography operations during
No occupancy timesFar away from workplaceNight hours
Less occupancy timesHolidaysLunch Hours
Make wire fence / brick enclosure for regular radiography area.
Transportation of sources
Check source pencil is securely immobilized and locked in camera
Inform BARC (Baba Atomic Research Centre), Mumbai, if damage to the cameras during transport,
non-receipt of consignment in the reasonable time
Avoid Maintenance and servicing of radiographic equipment without consulting the Radiological
Safety Officer (RSO)
Cordoning the radiography area
Calculate the safe cordoning distance
Make barricades with warning signs
Make reflective signs during night time operation
Use survey meter to check radiation level at cordoned boundaries
Ensure adequate illumination
Safe Work Practices
Example Calculation
Iridium-192 of 20 curie is used in open field of Occasional Occupancy for a period of 5 hours per week. Calculate the cordon off distance. Take Public dose limit as 2mR/week and B as 40.
Cordon off distance in the direction of primary beam:D2 = (K x A x W) T / P
= (500 x 20 x 5) (1/16) / 2D = 39.5 m
Cordon off distance in the directions other than primary beam direction: D2 = (K x A x W)T / (P x B)
= (500 x 20 x 5) (1/16) / (2X40)D = 6.25 m
Source Strength
Nature of Human
Occupancy
Work Load
5 hrs/week
10 hrs/week
15 hrs/week
20 hrs/week
30 hrs/week
Cordon off distance (m)
5 Curie Full 37 52 66 74 93
Partial 18 26 33 36 47
Occasional 10 13 17 18 24
8 Curie Full 47 65 80 94 122
Partial 24 33 40 48 56
Occasional 12 16 20 24 28
10 Curie Full 53 74 90 100 126
Partial 26 37 45 52 63
Occasional 13 19 22 26 31
Cordon off distances for Open Field Radiography (Panoramic Exposure) (Iridium – 192)
Nature of Human Occupancy Occupancy Factor
Full 1
Partial 1/4
Occasional 1/16
Occupancy Factor for open field radiography
Ensure Following Industrial Radiography Information form
(Format attached)
Radiographer carries film badge / dosimeter
Radiographers dose limit is below the permissible limit ( chart shown in next
slide)
Radiographers follows the safety instruction strictly
Safe Work Practices
Continue…..
Ensure Operators undergoes regular medical check up as per BARC
Source is not handled by hand
When source is expose it is advised to
Stand behind buildings / steel / shielding materials
Stay away from source of radiation
Limit exposure for particular operator /day
Make use of full length cable provided between radiographic equipment and the control unit / panel
Operator aware about his dose records and reports of periodic medical exams
Safe Work Practices Continued..
Safe Work Practices
Make collimated exposure
Avoid panoramic exposure
Use full length camera
Use suitable supporting and fastening devises
Camera operation behind barriers
Plan well the activities to limit exposure time.
Use radiation survey meter to check the source returns to safe position
Organ
Dose Limit for adult radiography
workmen(rems/Year)
Dose Limit for Public
(rems/Year)
Bone morrow, Eye Lens 5 0.5
Skin, Bones & Thyroid 30 3
Hands, Forearms, Feet and Ankles
75 7.5
Other Organs 15 1.5
Maximum Permissible Dose Limit
Cumulative dose for an occupational worker can be (N-18) Rems, N is the age of the radiography workmen. On an average it shall not exceed 100 milli Rems per week, 1 ¼ Rems per calendar quarter and 5 Rems per year. 250 to 400 RADs are sufficient to make it fatal in 50% of the cases within 30 days. With 50 to 100 RADs, the skin will turn reddish and a little higher dose will make the hair fall.
LARSEN & TOUBRO LIMITED ECC DIVISION
Ref: PM-20-D Rev 00
INDUSTRIAL RADIOGRAPHY - INFORMATION FORM
(This form to be filled up by the concerned Radiography agency and submitted to the Site Safety Co-ordinator. two days before Radiography date) 1. Radiography work to be done for (Name of Contractor) M/s 2. Name of Radiography Agency M/s _______________________________________________ 3. Name of the Incharge of the Radiography agency Mr._______________________________________________ 4. Date & Time of Starting 5. Date & Time of Completion 6. Location of Radiography work and area demarcated and cordoned (Sketches and Distances to be provided) 7. Source strength ____________________ Curies 8. Area cordoned & Radiation warning signs displayed and flash lights provided ( if no, give reason) Yes _______ No _________ 9. Visual check & other Agencies working nearby informed (if no, give reasons) Yes_______ No _______ (Give Name of other Agencies informed) 10. Whether Dosimeter & Survey meter available at site(if no, give reasons) Yes_______ No _______ 11. Whether Film Badges are available with operators(if no, give reasons) Yes_______ No _______ 12. Any other special precautions taken
Signature _____________ Site Incharge of Radiographic Agency
Signature _____________ Site Incharge of Contractor
Signature _____________ Site Engineer of ECCD
Signature _____________ Site Safety Co-ordinator of ECCD
YOUR TIMETO
GET CLARIFIED
ANY Q ?